Laminar disc of mineral wool

ABSTRACT

A mineral wool article formed of a plurality of layers of mineral wool discs bonded into a laminated product, said layers having bent edges relative to the interior part of the layers.

United States Patent 1191 Haglnnd Feb. 18, 1975 1 1 LAMINAR DISC OF MINERAL WOOL |56| References Cited I75] lnventor: Ulf Karl Henrik Haglnnd. Skuvde, UNI/15D 514111153 PNI'ENTS Sweden 2,165,281) 7/1939 [,annzm 204/152 X 2.564.941 8/1951 Wellmzm 1 1 1 264/152 1731 Asslgnee Rockwm' Akmbolage Skovdei 3,141,811 7/1964 FOX 6161 161/010. 4 Sweden 3,345,643 10/1967 Bradley 161/44 x 3,383,272 5/1968 Gluck 161/44 [22] 1973 3,390,403 6/1968 Van Tilburg 264/163 x [21] Appl. No.; 353,535 3,642,560 2/1972 Marsh, Jr. et al 264/163 x Primary Examiner--Philip Dier [30] Foreign Apphcatlon Prmmy Data 81/ 2 Attorney, Agent, or Firm-Larson, Taylor and Hinds Apr. 24, 1972 Sweden 53 7 [57] ABSTRACT [52] Cl 31x ;3 A mineral wool article formed of a plurality of layers [5]] l t Cl B32; 3/04 B32b 19/02 of mineral wool discs bonded into a laminated prod- [58] "161/42 d 4 44 149 uct, said layers having bent edges relative to the interior part of the layers.

7 Claims, 4 Drawing Figures PATEmfnrmlams SHEET 10F 3 LAMINAR DISC OF MINERAL WOOL Mineral wool usually is produced by melting the material forming the mineral wool in an oven, said material for instance being glass, slags, different kinds of stones and so on, the melt being poured against a quickly rotating disc or drum, so that it will be thrown out therefrom in the form of fibres, or by bringing said melt into a quick stream of gas or air, or by both of these steps. The most usual manner is first to fibrate the mineral melt by means of a series of rotating drums, and thereafter, by means of a stream of air, to carry away the spun material fromthe drum, whereby it is deposited on a continuously movable conveyor band, on which the mineral wool will form a mat. On its way from the spinning apparatus to the conveyor band, the mineral wool is often sprayed with a binder means in the form of a solution of plastic, which, at a later time .during the procedure of production, should be cured.

Convention binders for this purpose such as disclosed, for instance, in US. Pat. No. 3,383,272, may be used.

On the conveyor band, therefore, the spun mineral wool will deposit itself in the form of loops or bents of fibres, which will be positioned more or less close to parallel with the level of the conveyor band, whereby a decisive sheeting of the mineral wool in the mat will be created, said sheets running at least substantially in parallel to each other as well as to the level of the conveyor band. It has been usual that the curing of the binding means takes place, when the mineral wool, perhaps after compression, leaves the conveyor band, and this curing therefore as a rule took place by the mat being passed through a curing oven. In many a case the mat is not at all compressed or only unessentially compressed, but instead it is sewn between layers of paper or other suitable material to be used in its strongly porous state.

Dependent upon the range of use and the manner of use of the mineral wool, however, one has also taken steps for orientation of the layer direction either in the level of the compressed mineral wool discs or perpendicularily to said level. As a matter of fact, it is characteristic to such a compressed and cured mineral wool that it has essentially different rigidity against loads in different directions. Thus, one will get a greater deformation, when the load acts perpendicularily to the extension of the fibre levels than when the load acts in parallel to this level. If the fibre levels are in parallel to the level of the mineral wool disc, then this load and deformation distribution may for instance be desired in such cases when the mineral wool disc should be positioned between a pair of rulers in a building frame work. Then, one has to cut the mineral wool disc a little bigger than the free distance between the rulers, and pressing the disc between said rulers after some small deformation by pressing down the disc onto the bottom of the frame. The disc will then span itself outwardly against the sides of the rulers and in this way be effectively locked in place. Usually, one also wants that the thickness of the disc should be a little overdimensioned, so that, when a panel is attached by means of nails to the disc, this disc should be compressed in the direction of its thickness, but this compression will, in relation to the dimension of the disc in the compression direction, be of essentially greater extent.

In other cases, however, one wants to have the contrary properties of the disc. One has then proposed so called laminar products: One cuts out from the perhaps not yet cured mineral wool mat strips, which are turned about their own longitudinal axis by 90 and thereafter again attached to each other, perhaps under compression, so that the fibre levels of said discs will run perpendicularily to the level proper of the mineral wool disc. Perhaps, the cutting in strips and the turning of said strips could also take place after curing has taken place. A typical range of use of such laminar products of mineral wool is for insulation in floors. The insulation layer in the form of the mineral wool disc. in these cases, should be capable of carrying up rather great loads and thereby to be executed for rather great strains in a direction perpendicular to the level of the disc. The load thereby was executed by the pressure from a pressure distribution plate of some kind. As this load will attack the plate in a direction, parallel to the fibre level direction, the disc has a great power of assuming the said loads. On the other side, the insulation discs of mineral wool should be possible to adapt tightly adjacent to each other in the floor,'and they must then be compressible to some extent in sideward direction.

Another field, within which one has found use of mineral wool laminar products suitable, is as intermediate walls of some kinds, especially bulk heads in sea going vessels.

The property of the laminar discs to be strongly sheeted, however, causes a weakness, as far as they rather easily split themselves up in the level of the layers under load conditions, suitable for such splitting. These load conditions regularily happen to exist when handling them, for instance during transportation, moving and so on, and in work, thereby the discs are subjected to bending. Bending and splitting in combination makes the breakage of the disc, especially when the bending strain causes pull strains perpendicularily to the fibre layers. Therefore, it is of great importance that the laminer discs should have a rigidity against such splitting and breaking following thereafter under influence of a bending, which one believed according to the technics used hitherto, only to be capable of ensuring by making the discs with high rigidityagainst bending. For this purpose one has proposed to cover or line the discs on at least one side but preferably on both sides with a surface liner of high rigidity, for instance glass fibre weft, which had to take up the pull load created at the tendency of bending the disc.

It is in the nature of matters that it means a complication in the production of mineral wool discs of this type to provide them with such an inforcement surface layer, and that one therefore has. a good reason to try to find other possibilities for doing away with the disadvantages just mentioned.

The present invention refers to a laminar product of mineral wool, which has the required rigidity against bending in all directions without. therefore being covered by any extra surface layer.

According to the invention, the fibre layers are bent at the edges of the mineral wool discs in relation to the fibre layers in the interior parts of the mineral wool that all different kinds of modifications may occur within the frame of the invention. In the drawing FIG. 1 shows an arrangement for the production of mineral wool discs according to the invention in a strongly simplified and schematical form, whereas FIG. 2 shows a section through a mineral wool disc according to the invention, also in strongly simplified and schematical form, and

FIG. 3 shows an enlargement of the edge part of the mineral wool disc according to FIG. 2 in a way, approaching the one existing in practice.

FIG. 4 shows a variation of the mineral wool disc according to FIG. 2. 1

In the arrangement according to FIG. 1, a path of mineral wool will be derived from a spinner machine. As the character of this machine is assumed to be well known to the man skilled in the art, it has not been shown in the drawing. The path 10 is conveyed in the direction of the arrow 11, for instance with intermittent feeding. Each time when the path 10 is in stand still, a strip 12 is cut off from the path by means of a knife device 13. This strip thus has a length perpendicularily to the level of the paper corresponding to the width of the mineral wool path 10. Before the mineral wool path is continuing its movement, an elongated piston 14 enters. said piston having a bent profile on its attack surface 15, during movement in the direction of the arrow 16 for displacement of the strip 12 into the funnel-formed mouth 36 of a channel 37.

By clamping action between the sides of the channel 36, 37, on the one hand, and the bent profile of the piston 14, on the other hand, thereby a bending of the edges 18, 18" of the mineral wool strip will take place, which is shown at 12' in the interior of the channel 17. To this deformation, of course, also the pressure from the already deformed strips, placed in advance thereof, adds, for instance the strips 19, 20 and so on. The piston immediately moves back after having introduced the strip 12 into the position 12,'and material for a new strip is fed from the mineral wool path 10 and cut off by means of the knife device 13, and the procedure is repeated.

In this way a mineral wool disc is built up, which is not yet cured, but which comprises cross-wardly placed laminae I2 l9 20 and so on, and which will successively move forward in the channel 37, which preferably is formed by two continuously or intermittently movable bands, one on each side of the disc to be formed. The mineral wool disc will obtain a width, equal to the length of the strips, and a thickness equal to the free distance between the walls of the channel 37.

The curing of the binding means existing in the mineral wool path takes place in an oven 21 of traditional kind. and the mineral wool disc thus continuously moved forwardly through the oven is cut by means of a severing device 22 into discs 23 of adapted length.

One such disc is shown in strongly schematical form and with respect to width as well as length strongly shortened form in FIG. 2, in which every second layer has been marked. It is seen that the disc is composed by laminae or layers 24, 25, 26 and so on, the layer direction of which runs substantially such as is usual in so called cross laminated products of mineral wool, but at the edges the layers are bent over and somewhat compressed, whereby the disc will get an increased rigidity against bending in the bending direction, marked by the arrow 27. From the detail shown in FIG. 3 one will see that the bending of the fibre layers causes a compression, and that the fibre layers at the surface will overlap each other, so that the splitting tendency will practically be annulated. This splitting influence may for instance be caused due to the weight proper of the disc, if one elevates the mineral wool disc when moving same by gripping it at each end 28 and 29, respectively.

It is easily seen that a laminar disc of the structure, shown in FIG. 2, will have a very essentially decreased splitting tendency at bending along the arrow 27 in relation .to conventional laminar products, but nevertheless it will be weaker when bent in this direction than in the direction perpendicular thereto in the level of the disc. This difference, however, may be equalized by causing a bending also in a level, perpendicular to the level, which has been shown as the only bending level in FIG. 2. Such a mineral wool disc is schematically shown in FIG. 4. By giving the piston 14, FIG. 1, a profile in a direction perpendicular to the level of the paper in the form of a wave-formed space curve. for instance having S-shape or integral shape, one has caused that at the compression in the channel 37 will not only the bending shown in FIG. 2 be created at the edges, but in addition thereto also a bending 30, 31, 32, preferably in another shape and in a level, perpendicular to the bending level in FIG. 2. Thereafter one can cut the mineral wool disc to be formed rather independently of what dimension should be called its long side or its short side respectively. This mineral wool disc retains all of the properties, characteristic to the laminar product of mineral wool, but it is free to a high degree from any risk for being broken or split during less careful handling. In addition thereto one has by very simple means been capable of avoiding the expensive and time-consuming method, earlier used, by lining the mineral wool disc in in a surface layer, glued thereto, for instance a glass fibre web.

Even if the last mentioned bending 30, 31, 32 of the fibre levels in the mineral wool disc have been shown in FIG. 4 to be wave-shaped, it is also possible to give them another shape, for instance saw-tooth-shape.

In practical tests with the invention it has proved that the amplitude of the curves, which are followed by the fibre levels, should suitably amount to half part of the thickness of the disc or a little more, but preferably not less. The conception amplitude thereby refers to the middle line of the fibre layers, projected on the main level of the product. The wave length should suitably be at least equal to the amplitude and not more than four-fold the amplitude, preferably about the double of the amplitude, in order that the best result shall be achieved.

In the above described forms of execution of the invention it has proved in practical tests suitable to give the bent edge parts ofthe mineral wool disc a width 33 of not less'than l/20 and not more than l/5 of the thickness of the mineral wool disc.

I claim:

1. An article of mineral wool comprising a plurality of layers of fibrous mineral wool discs bonded together to form a laminated product, said layers of said laminated product having bent edges relative to the interior part of said layers, said interior part comprising a major part of the width of said laminated product.

5. An article according to claim 4 wherein said layers are wave shaped.

6. An article according to claim 5, in which the amplitude of said wave-shaped layers is at least equal to half of the thickness of the laminated product.

7. An article according to claim 5, in which the wave length of the laminated product is at least equal to the amplitude up to four-fold the amplitude. 

1. An article of mineral wool comprising a plurality of layers of fibrous mineral wool discs bonded together to form a laminated product, said layers of said laminated product having bent edges relative to the interior part of said layers, said interior part comprising a major part of the width of said laminated product.
 2. An article according to claim 1, in which the layers run at least substantially perpendicularly to the level proper of the laminated product.
 3. An article according to claim 1, in which the bent edges have a width of at least 1/20 and up to 1/5 of the thickness of the laminated product.
 4. An article according to claim 1 in which said layers bend perpendicular to a section of the laminated product.
 5. An article according to claim 4 wherein said layers are wave shaped.
 6. An article according to claim 5, in which the amplitude of said wave-shaped layers is at least equal to half of the thickness of the laminated product.
 7. AN ARTICLE ACCORDING TO CLAIM 5, IN WHICH THE WAVE LENGTH OF THE LAMINATE PRODUCT IS AT LEAST EQUAL TO THE AMPLITUDE UP TO FOUR-FOLD THE AMPLITUDE. 